Mote Searches for Traces of Red Tide in Sarasota

Mote Marine Laboratory has detected Karenia brevis, the organism that causes Florida red tide, in water collected Wednesday from one area offshore of Sarasota County in Venice. The Lab will continue to monitor for K. brevis in local Sarasota waters.

Water samples that Mote collected by boat on Wednesday, Sept. 28 showed a high concentration of K. brevis at a single location about four miles offshore of Venice. No concentrations of K. brevis were detected in five other locations sampled Wednesday to the south, including waters offshore from Manasota Beach, a Mote press release said.

Mote scientists deployed an autonomous underwater vehicle (AUV) nicknamed “Waldo” at 11:30 a.m. Thursday, Sept. 29 in waters about two miles west of Siesta Key, to patrol for harmful algae for about one week, the news release said. The glider will travel an offshore course ranging from south of Manasota Beach to Sarasota. The AUV carries an instrument designed at Mote that samples the water continuously and uses a satellite uplink to send data to Mote scientists on which algae species are present.

Findings will be provided to the Florida Fish and Wildlife Conservation Commission (FWC), which posts bi-weekly updates on Florida red tide by region. The next update is expected this afternoon, Sept. 30. FWC’s update on Tuesday, Sept. 27, said medium concentrations of K. brevis were found recently in a water sample collected from Manasota Beach. The sample was collected by the Sarasota County Health Department and provided to Mote Marine Laboratory, which analyzed the sample.

According to Mote, the last time medium or higher concentrations of K. brevis were found locally was when a small, drifting patch was found in winter 2009 in Sarasota County waters. The patch was short-lived and did not notably affect wildlife or humans. The last significant red tide bloom for Sarasota County was in 2006.